Updated

As President Obama landed in Mississippi for his fourth trip to the Gulf Coast to survey oil spill damage, BP outlined a plan it said would speed up the containment effort so that more than 50,000 barrels a day can be pumped to the surface by the end of June.

The outline came after the Coast Guard on Friday demanded the company figure out ways to accelerate the process. The cap on the blown-out well is said to be capturing about 15,000 barrels a day -- but plenty more is still leaking into the Gulf of Mexico.

Under the revised schedule, BP claims it can capture between 40,000 and 53,000 barrels a day by the end of this month. BP wasn't expected to reach that capacity until mid-July under the earlier plan. The new estimate, detailed in a letter to the Coast Guard dated Sunday, also claims the energy giant will be able to capture as much as 80,000 barrels a day by mid-July.

The Obama administration said BP was responding to its order from Friday, in which Coast Guard Rear Adm. James Watson told the company that "every effort must be expended to speed up" the rate of containment.

"After being directed by the administration to move more quickly, BP is now stepping up its efforts to contain the leaking oil," an administration official said Monday, adding that the new plan has enough backup in place to account for bad weather and "unforeseen circumstances."

"This administration has continuously demanded strategies and responses from BP that fit the realities of this catastrophic event, for which BP is responsible. We will continue to hold BP accountable and bring every possible resource and innovation to bear," the official said.

BP, in its letter, said it would mobilize a vessel from South America to store oil, in addition to two more lightering tankers -- used to transfer cargo between ships -- from Europe and other equipment.

Click here to read the letter.

BP Chief Operating Officer Doug Suttles said in the letter that the company believes "this plan is responsive to your order," but cautioned that the firm was outside its comfort zone.

"The risks of operating multiple facilities in close proximity must be carefully managed," he wrote. "Several hundred people are working in a confined space with live hydrocarbons on up to 4 vessels. This is significantly beyond both BP and industry practice.

"We will continue to aggressively drive schedule to minimize pollution, but we must not allow this drive to compromise our number one priority, that being the health and safety of our people," he wrote.

BP is facing increasing political and public pressure not only to speed up the rate of containment but to pledge more money to help those suffering economic losses from the spill. Obama is pressing the company to set up an escrow account to pay for lost income to local businesses, a plan he will describe during an address to the nation from the Oval Office on Tuesday.

Leading up to his address, the president will tour Mississippi, Alabama and Florida to survey the damage. He is set to arrive in Biloxi, Miss., shortly before noon on Monday.

To this point, the president had only visited the Louisiana coast. Florida Republican Sen. George LeMieux said that when the president visits his state on Tuesday, he plans to press him on why the administration is not allowing in more oil skimmers to clean up the damage.

Four hundred skimming boats are at work in the Gulf cleaning up the oil, but local officials have been pleading with the federal government to bring in more -- one problem may be that foreign ships are barred from working in U.S. coastal waters by a 1920s law known as the Jones Act.

Officials say they are prepared to waive the act if necessary, but White House energy adviser Carol Browner told Fox News on Friday that so far no request from the Coast Guard has been made to do so.

LeMieux told Fox News on Monday that U.S. skimmers are available as well and questioned why more boats are not being deployed.

"There's thousands of skimmers in the United States and thousands of skimmers around the world," he said. "Why aren't they headed to the Gulf of Mexico? It doesn't' make any sense to me."